|Boundary between two mapped units that was observed, the location of which is well known and is described in Positional_Accuracy
|crest of crater in cinder cone
|crest of crater in cinder cone
|a dike composed of map unit Km
|dike composed of map unit QTbi
|dike composed of map unit ZYa
|fault, approx. located
|Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset. The existence is inferred from structural, stratographic, of lineament relations. Locational accuracy is approximate
|Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset. Locational accuracy is well located
|Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset. The fault is obscured by overlying map units, so it is not well-located
|Edge of mapped area, used to bound polygons at the edge of the map database
|A bed composed of map unit Tsd
|s.s. fault, r.l., certain
|Structural boundary between mapped units or structural discontinuity within a mapped unit that has experienced relative offset in a predomintate right lateral, strike slip direction. Locational accuracy is well located
|Playa deposits in volcanic craters (Holocene)
|Unit 4 (Holocene)--Alluvial fill of active channels
|Unit 3 (Holocene to Pleistocene)--Undissected to little dissected alluvial deposits of unstratified to weakly stratified sand and gravel.
|Subunit 3b-Little dissected deposits about 1 to 2 m above active channels.
|Subunit 3a--Little dissected deposits 1 to 3 m above active channels.
|Unit 2 (Pleistocene)--Moderately to well dissected alluvial deposits of sand and gravel.
|Subunit 2c-Moderately dissected alluvial deposits about 1 to 5 m above adjacent drainages.
|Subunit 2b-Moderately dissected alluvial deposits about 2 to 6 m above adjacent drainages.
|Subunit 2a-Generally well-dissected alluvial deposits 5 to 10 m above adjacent drainages, or 1 to 5 m above adjacent Q2b deposits.
|Talus and colluvial deposits derived from cinder cones and basalt flows (Holocene to early Pliocene)
|Unit 1 (Pleistocene to Pliocene)--Dissected deposits with no relic pavement, 5 to 10 m above adjacent drainages.
|Conglomerate and arkosic sandstone (Quaternary or Pliocene?)
|Lake deposits of Valley Wells basin (Pleistocene to Pliocene)
|Coarse ash and lapilli tuff (Pleistocene)
|Deposits of red oxidized scoria and black unoxidized scoria consisting of pebble to cobble size fragments
|Deposits of blocks and bombs, consisting of boulder-size fragments as much as 5 m in diameter.
|Pyroclastic breccia (Pleistocene to late Pliocene)
|Lava flow (Pleistocene to late Pliocene)
|Tuffaceous breccia (Pleistocene to late Miocene)
|Tephra (early Pliocene to late Miocene)
|Pyroclastic breccia (early Pliocene to late Miocene)
|Lava flow (early Pliocene to late Miocene)
|Volcanic rocks (middle Miocene)
|Peach Springs Tuff of Young and Brennan (1974) (early Miocene)
|Sedimentary rocks-Fine-grained sandstone, siltstone, shale, fresh water limestone locally present near base of deposits.
|Limestone (Permian to Devonian)
|Siliciclastic rocks (Cambrian and Late Proterozoic)
|Basalt dikes and plugs (Holocene? to late Miocene)
|Pseudotachylite (Tertiary? or Cretaceous?)
|Rhyolitic dikes (Tertiary? or Cretaceous?)
|Mafic dikes (Tertiary? or Cretaceous?)
|Mafic and intermediate dikes (Cretaceous)
|Aplite, pegmatite, and fine- to medium-grained biotite monzogranite dikes (Cretaceous)
|Felsic members of Teutonia batholith
|Intermediate members of Teutonia batholith
|Mafic member of Teutonia batholith
|Alaskite dike (Late Proterozoic? or Middle Proterozoic?)
|Undivided mafic and felsic gneiss
|Sample for K/Ar analysis
|horizontal (flat) bedding
|vert foliation and bedding
|Range of values
|Range of values
|degrees, based on the 'right-hand-rule'
The purpose of this dataset is to archive previous geologic mapping in the area and to enable the further use, reclassification, and analysis of existing geologic map data in the area.
Are there legal restrictions on access or use of the data?
Use_Constraints:Acknowledgement of the U.S. Geological Survey; uses of this digital geologic map should not violate the spatial resolution of the data. Although the digital form of the data removes the constraint imposed by the scale of a paper map, the detail and accuracy inherent in map scale are also present in the digital data. The fact that this database was edited at a scale of 1:24,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:24,000 will not yield greater real detail, although it may reveal fine-scale irregularities below the intended resolution of the database. Similarly, where this database is used in combination with other data of higher resolution, the resolution of the combined output will be limited by the lower resolution of these data.
This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
This database, identified as "Digital Version of 'Open-File Report 92- 181: Geologic Map of the Indian Spring Quadrangle, San Bernardino County, California'" has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review.
Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use.
|Geologic units, structural features and measurements, and sample locations in format ARCE (version 8.0) Size: 2